FAN ASSEMBLY COMPRISING ANNULAR NOZZEL AND CEILING MOUNT
FIELD OF THE INVENTION
The present invention relates to a fan assembly for generating an air flow within a room.
In its preferred embodiment, the fan assembly is in the form of a ceiling fan.
BACKGROUND OF THE INVENTION
A number of ceiling fans are known. A standard ceiling fan comprises a set of blades
mounted about a first axis and a drive also mounted about the first axis for rotating the
set of blades. Another type of ceiling fan generates a column of air downwardly into a
room. For example, GB 2,049,161 describes a ceiling fan which has a domed support
which is suspended from a ceiling, and a motor-driven impeller which is coupled to the
inner surface of the support. An air stream emitted from the impeller is conveyed
through a generally cylindrical body containing an array of air passages to generate a
linear air stream which is emitted from the ceiling fan.
SUMMARY OF THE INVENTION
In a first aspect, the present invention provides a fan assembly for generating an air flow
within a room, the fan assembly comprising:
an air inlet section comprising an air inlet, an impeller, and a motor for rotating
the impeller about an impeller axis to draw an air flow through the air inlet;
an annular nozzle comprising an inner wall, an outer wall extending about the
inner wall, at least one air outlet for emitting the air flow, and an interior passage
located between the inner wall and the outer wall for conveying the air flow to said at
least one air outlet, the inner wall defining a bore through which air from outside the
nozzle is drawn by the air flow emitted from said at least one air outlet; and
a support assembly for supporting the air inlet section and the nozzle on a ceiling
of the room.
The air flow emitted from the annular nozzle entrains air surrounding the nozzle, which
thus acts as an air amplifier to supply both the emitted air flow and the entrained air tothe user. The entrained air will be referred to here as a secondary air flow. The
secondary air flow is drawn from the room space, region or external environment
surrounding the nozzle. The emitted air flow combines with the entrained secondary air
flow to form a combined, or total, air flow projected forward from the nozzle. A
portion of the secondary air flow is drawn through the bore of the nozzle, whereas other
portions of the secondary air flow pass around the outside of the outer wall and in front
of the nozzle to combine with the emitted air flow downstream of the bore.
The inner wall is preferably annular in shape to extend about and define the bore. The
interior passage is preferably located between the inner wall and the outer wall, and
more preferably is defined, at least in part, by the inner wall and the outer wall. The
nozzle comprises at least one air inlet for receiving an air flow. The outer wall
preferably defines the air inlet(s). For example, the, or each air inlet may be in the form
of an aperture formed in the outer wall. The nozzle preferably comprises an air outlet
section extending between the inner wall and the outer wall. The air outlet section may
be a separate component connected between the inner wall and the outer wall.
Alternatively, at least part of the air outlet section may be integral with one of the inner
wall and the outer wall. The air outlet section preferably forms at least part of an end
wall, more preferably a lower end wall, of the nozzle. The air outlet section preferably
defines, at least in part, at least one air outlet of the nozzle for emitting the air flow. The
air outlet(s) may be formed in the air outlet section. Alternatively, the air outlet(s) may
be located between the air outlet section and one of the inner wall and the outer wall.
The air inlet(s) of the nozzle are preferably substantially orthogonal to the air outlet(s)
of the nozzle.
The air outlet section is preferably configured to emit the air flow away from the bore
axis, preferably in the shape of an outwardly tapering cone. We have found that the
emission of the air flow from the nozzle in a direction which extends away from the
bore axis can increase the degree of the entrainment of the secondary air flow by the
emitted air flow, and thus increase the flow rate of the combined air flow generated by
the fan assembly. References herein to absolute or relative values of the flow rate, orthe maximum velocity, of the combined air flow are made in respect of those values as
recorded at a distance of three times the diameter of the air outlet of the nozzle.
Without wishing to be bound by any theory, we consider that the rate of entrainment of
the secondary air flow may be related to the magnitude of the surface area of the outer
profile of the air flow emitted from the nozzle. When the emitted air flow is outwardly
tapering, or flared, the surface area of the outer profile is relatively high, promoting
mixing of the emitted air flow and the air surrounding the nozzle and thus increasing the
flow rate of the combined air flow. Increasing the flow rate of the combined air flow
generated by the nozzle has the effect of decreasing the maximum velocity of the
combined air flow. This can make the nozzle suitable for use with a fan assembly for
generating a flow of air through a room or an office.
The air outlet section preferably comprises an inner section connected to the inner wall,
and an outer section connected to the outer wall. The at least one air outlet may be
located between the inner section and the outer section of the annular wall. At least part
of the inner section may taper away from the bore axis. An angle of inclination of this
part of the inner section to the bore axis may be between 0 and 45°. This part of the
inner section preferably has a shape which is substantially conical. The air outlet
section may be arranged to emit the air flow in a direction which is substantially parallel
to this part of the inner section. The outer section is preferably substantially orthogonal
to the bore axis.
The at least one air outlet preferably extends about the bore axis. The nozzle may
comprise a plurality of air outlets angularly spaced about the bore axis, but in a
preferred embodiment the nozzle comprises a substantially annular air outlet.
The at least one air outlet may be shaped to emit air in a direction extending away from
the bore axis. A portion of the interior passage which is located adjacent the air outlet
may be shaped to direct the air flow through the air outlet so that the emitted air flow is
directed away from the bore axis. To facilitate manufacturing, the air outlet section maycomprise an air channel for directing the air flow through the air outlet. The air channel
is preferably inclined to the bore axis, and preferably has a shape which is generally
frusto-conical. An angle subtended between the air channel and the bore axis is
preferably between 0 and 45°. In a preferred embodiment, this angle is around 15°.
The interior passage preferably extends about the bore axis, and preferably surrounds
the bore axis. The interior passage may have any desired cross-section in a plane
passing through the bore axis. In a preferred embodiment the interior passage has a
substantially rectangular cross-section in a plane passing through the bore axis.
The nozzle may comprise a chord line extending midway between the inner wall and the
outer wall of the nozzle. The at least one air outlet is preferably located between the
bore axis and the chord line.
The support assembly preferably comprises a mounting bracket which is attachable to
the ceiling of the room. This mounting bracket may be in the form of a plate which is
attachable to the ceiling, for example using screws. The support assembly is preferably
configured to support the air inlet section and the nozzle so that the impeller axis is at an
angle of less than 90° to the mounting bracket, more preferably so that the impeller axis
is at an angle of less than 45° to the mounting bracket. In one embodiment, the support
assembly is configured to support the air inlet section and the nozzle so that the impeller
axis is substantially parallel to the mounting bracket. The bore axis is preferably
substantially orthogonal to the impeller axis, and so the support assembly may be
configured to support the air inlet section and the nozzle so that the axis of the bore is
substantially orthogonal to the mounting bracket. The air inlet section and the nozzle
preferably have substantially the same depth as measured along the bore axis.
This can allow the fan assembly to be arranged so that it lies substantially parallel to a
horizontal ceiling to which the mounting bracket is attached. The nozzle may be
located relatively close to the ceiling, reducing the risk of a user, or an item being
carried by the user, coming into contact with the nozzle.The air inlet of the air inlet section may comprise a single aperture, or a plurality of
apertures through which the primary air flow is drawn into the air inlet section. The air
inlet is preferably arranged so that the impeller axis passes through the air inlet, more
preferably so that the impeller axis is substantially orthogonal to the air inlet of the air
inlet section.
To minimise the size of the air inlet section, the impeller is preferably an axial flow
impeller. The air inlet section preferably comprises a diffuser located downstream from
the impeller for guiding the air flow towards the nozzle. The air inlet section preferably
comprises an outer casing, a shroud extending about the motor and the impeller, and a
mounting arrangement for mounting the shroud within the outer casing. The diffuser
preferably comprises an inner annular wall for supporting the motor, an outer annular
wall connected to the shroud, and a plurality of curved vanes located between the inner
and outer walls. The casing and the shroud are preferably substantially cylindrical.
The mounting arrangement may comprise a plurality of mounts located between the
outer casing and the shroud, and a plurality of resilient elements connected between the
mounts and shroud. In addition to positioning the shroud relative to the outer casing,
preferably so that the shroud is substantially co-axial with the outer casing, the resilient
elements can absorb vibrations generated during use of the fan assembly. The resilient
elements are preferably held in a state of tension between the mounts and the shroud,
and preferably comprise a plurality of tension springs each connected at one end to the
shroud and at another end to one of the supports. Means may be provided for urging
apart the ends of the tension springs in order to maintain the springs in a state of tension.
For example, the mounting arrangement may comprise a spacer ring which is located
between the mounts for urging apart the mounts, and thereby urging one end of each
spring away from the other end.
In a second aspect, the present invention provides apparatus for supporting a motor
within a casing, the apparatus comprising a shroud connected to and extending about the
motor, a plurality of mounts located between the casing and the shroud, and a pluralityof resilient elements connected between the mounts and the shroud, and wherein the
resilient elements are held in a state of tension between the mounts and the shroud.
The air inlet section is preferably located between the support assembly and the nozzle.
One end of the air inlet section is preferably connected to the support assembly, with the
other end of the air inlet section being connected to the nozzle. The air inlet section is
preferably substantially cylindrical.
The support assembly may comprise an air passage disposed upstream of the air
outlet(s). The air flow generated by the impeller passes through the air passage.
Depending on the relative positions of the support assembly and the air inlet section, the
air passage may convey air to or from the air inlet section. For example, the air passage
of the support assembly may be substantially co-axial with an air passage of the air inlet
section which houses the impeller and the motor.
The nozzle is preferably rotatable relative to the support assembly to allow a user to
change the direction in which the primary air flow is emitted into a room. The nozzle is
preferably rotatable relative to the support assembly about a rotational axis and between
a first orientation in which the air flow is directed away from the ceiling and a second
orientation in which the air flow is directed towards the ceiling. For example, during
the summer the user may wish to orient the nozzle so that the air flow is emitted away
from a ceiling to which the fan assembly is attached and into a room so that the air flow
generated by the fan assembly provides a relatively cool breeze for cooling a user
located beneath the fan assembly. During the winter however, the user may wish to
invert the nozzle through 180° so that the air flow is emitted towards the ceiling to
displace and circulate warm air which has risen to the upper portions of the walls of the
room, without creating a breeze directly beneath the fan assembly.
The nozzle may be inverted as it is rotated between the first orientation and the second
orientation. The rotational axis of the nozzle is preferably substantially orthogonal to
the bore axis, and is preferably substantially co-planar with the impeller axis.The nozzle may be rotatable relative to both the air inlet section and the support
assembly. Alternatively, the air inlet section may be connected to the support assembly
so that both the air inlet section and the nozzle are rotatable relative to the support
assembly.
The support assembly preferably comprises a ceiling mount for mounting the fan
assembly on a ceiling, an arm having a first end connected to the ceiling mount, and a
body connected to a second end of the arm and the nozzle. The body may be connected
directly to the nozzle, or to the air inlet section. The body is preferably an annular body,
and which includes the air passage for conveying the air flow to the air outlet(s).
The body is preferably pivotable relative to the arm to move the nozzle between a raised
position and a lowered position. The nozzle and the air inlet section may therefore be
pivotable relative to the mounting bracket of the support assembly. Lowering the
nozzle can increase the distance between the nozzle and a ceiling to which the fan
assembly is attached, and so allow the nozzle to be rotated relative to the support
assembly without coming into contact with the ceiling. Lowering the nozzle can also
facilitate its rotation by the user.
The nozzle and the air inlet section are preferably pivotable about a pivot axis which is
substantially orthogonal to the impeller axis. The body is thus preferably pivotable
relative to the arm about a pivot axis which is substantially orthogonal to the impeller
axis. The pivot axis is preferably substantially orthogonal to the bore axis of the nozzle.
The impeller axis is preferably substantially horizontal when the nozzle is in the raised
position and the support assembly is connected to a substantially horizontal ceiling.
The body may be pivotable about an angle in the range from 5 to 45° to move the
nozzle from the raised position to the lowered position. Depending on the radius of the
outer wall of the nozzle, the body may pivot about an angle in the range from 10 to 20°
to move the nozzle from the raised position to the lowered position. The bodypreferably houses a releasable locking mechanism for locking the body relative to the
arm so that the nozzle is maintained in its raised position. The locking mechanism is
releasable by the user to allow the nozzle to be moved to its lowered position. The
locking mechanism is preferably biased towards a locking configuration for locking the
body relative to the arm so that the nozzle is maintained in its raised position. The
locking mechanism is preferably arranged to return automatically to the locking
configuration when the nozzle is moved from the lowered position to the raised
position.
The arm is preferably rotatably connected to the ceiling mount. The arm is preferably
rotatable relative to the ceiling mount about a rotational axis, and the arm is preferably
inclined to the rotational axis. Consequently, as the arm is rotated about its rotational
axis, the nozzle and the air inlet section orbit about the rotational axis. This allows the
nozzle to be moved to a desired position within a relatively wide annular area. The arm
is preferably inclined at an angle in the range from 45 to 75° to the rotational axis to
minimise the distance between the nozzle and the ceiling. The rotational axis of the arm
is preferably substantially orthogonal to the pivot axis of the body.
Features described above in connection with the first aspect of the invention are equally
applicable to the second aspect of the invention, and vice versa.
BRIEF DESCRIPTION OF THE DRAWINGS
Preferred features of the invention will now be described, by way of example only, with
reference to the accompanying drawings, in which:
Figure 1 is a front perspective view, from above, of a ceiling fan;
Figure 2 is a left side view of the ceiling fan mounted to a ceiling, and with an annular
nozzle of the ceiling fan in a raised position;
Figure 3 is a front view of the ceiling fan;Figure 4 is a rear view of the ceiling fan;
Figure 5 is a top view of the ceiling fan;
Figure 6 is a side sectional view of the ceiling fan, taken along line A-A in Figure 5;
Figure 7 is a close up view of area A indicated in Figure 6, illustrating the motor and
impeller of an air inlet section of the ceiling fan;
Figure 8 is a close up view of area B indicated in Figure 6, illustrating the air outlet of
the annular nozzle;
Figure 9 is a close up view of area D indicated in Figure 6, illustrating the connection
between a ceiling mount and an arm of a support assembly of the ceiling fan;
Figure 10 is a side sectional view of the ceiling mount and the arm of the support
assembly, taken along line C-C in Figure 6;
Figure 11 is a close up view of area C indicated in Figure 6, illustrating a releasable
locking mechanism for retaining the annular nozzle in the raised position;
Figure 12 is a sectional view of the locking mechanism, taken along line B-B in Figure
11; and
Figure 13 is a left side view of the ceiling fan mounted to a ceiling, and with an annular
nozzle of the ceiling fan in a lowered position.
DETAILED DESCRIPTION OF THE INVENTION
Figures 1 to 5 illustrate a fan assembly for generating an air flow within a room. In this
example, the fan assembly is in the form of a ceiling fan 10 which is connectable to aceiling C of a room. The ceiling fan 10 comprises an air inlet section 12 for generating
the air flow, an annular nozzle 14 for emitting the air flow, and a support assembly 16
for supporting the air inlet section 12 and the nozzle 14 on the ceiling C of the room.
The air inlet section 12 comprises a generally cylindrical outer casing 18 which houses a
system for generating a primary air flow which is emitted from the nozzle 14. As
indicated in Figures 1, 2 and 5, the outer casing 18 may be formed with a plurality of
axially extending reinforcing ribs 20 which are spaced about the longitudinal axis L of
the outer casing 18, but these ribs 20 may be omitted depending on the strength of the
material from which the outer casing 18 is formed.
With reference now to Figures 6 and 7, the air inlet section 12 houses an impeller 22 for
drawing a primary air flow into the ceiling fan 10. The impeller 22 is in the form of an
axial flow impeller which is rotatable about an impeller axis which is substantially co-
linear with the longitudinal axis L of the outer casing 18. The impeller 22 is connected
to a rotary shaft 24 extending outwardly from a motor 26. In this embodiment, the
motor 26 is a DC brushless motor having a speed which is variable by a control circuit
(not shown) located within the support assembly 16. The motor 26 is housed within a
motor casing comprising a front motor casing section 28 and a rear motor casing section
30. During assembly, the motor 26 is inserted first into the front motor casing section
28, and the rear motor casing section 30 is inserted subsequently into the front casing
section 28 to both retain and support the motor 26 within the motor casing.
The air inlet section 12 also houses a diffuser located downstream from the impeller 22.
The diffuser comprises a plurality of diffuser vanes 32 which are located between an
inner cylindrical wall 34 and an outer cylindrical wall of the diffuser. The diffuser is
preferably moulded as a single body, but alternatively the diffuser may be formed from
a plurality of parts or sections which are connected together. The inner cylindrical wall
34 extends about and supports the motor casing. The outer cylindrical wall provides a
shroud 36 which extends about the impeller 22 and the motor casing. In this example,
the shroud 36 is substantially cylindrical. The shroud 36 comprises an air inlet 38 atone end thereof through which the primary air flow enters the air inlet section 12 of the
ceiling fan 10, and an air outlet 40 at the other end thereof through which the primary
air flow is exhausted from the air inlet section 12 of the ceiling fan 10. The impeller 22
and the shroud 36 are shaped so when the impeller 22 and motor casing are supported
by the diffuser, the blade tips of the impeller 22 are in close proximity to, but do not
contact, the inner surface of the shroud 36 and the impeller 22 is substantially co-axial
with the shroud 36. A cylindrical guide member 42 is connected to the rear of the inner
cylindrical wall 34 of the diffuser for guiding the primary air flow generated by the
rotation of the impeller 22 towards the air outlet 40 of the shroud 36.
The air inlet section 12 comprises a mounting arrangement for mounting the diffuser
within the outer casing 18 so that the impeller axis is substantially co-linear with the
longitudinal axis L of the outer casing 18. The mounting arrangement is located within
an annular channel 44 extending between the outer casing 18 and the shroud 36. The
mounting arrangement comprises first mount 46 and a second mount 48 which is axially
spaced along the longitudinal axis L from the first mount 46. The first mount 46
comprises a pair of interconnected arcuate members 46a, 46b which are mutually
axially spaced along the longitudinal axis L. The second mount 48 similarly comprises
a pair of interconnected arcuate members 48a, 48b which are mutually axially spaced
along the longitudinal axis L. An arcuate member 46a, 48a of each mount 46, 48
comprises a plurality of spring connectors 50, each of which is connected to one end of
a respective tension spring (not shown). In this example, the mounting arrangement
comprises four tension springs, with each of these arcuate members 46a, 48a comprising
two diametrically opposed connectors 50. The other end of each tension spring is
connected to a respective spring connector 52 formed in the shroud 36. The mounts 46,
48 are urged apart by an arcuate spacer ring 54 inserted into the annular channel 44
between the mounts 46, 48 so that the tension springs are held in a state of tension
between the connectors 50, 52. This serves to maintain a regular spacing between the
shroud 36 and the mounts 46, 48 while allowing a degree of radial movement of the
shroud 36 relative to the mounts 46, 48 to reduce the transmission of vibrations from the
motor casing to the outer casing 18. A flexible seal 56 is provided at one end of theannular channel 44 to prevent part of the primary air flow from returning to the air inlet
40 of the shroud 36 along the annular channel 44.
An annular mounting bracket 58 is connected to the end of the outer casing 18 which
extends about the air outlet 42 of the shroud 36, for example by means of bolts 60. An
annular flange 62 of the nozzle 14 of the ceiling fan 10 is connected to the mounting
bracket 58, for example, by means of bolts 64. Alternatively, the mounting bracket 58
may be integral with the nozzle 14.
Returning to Figures 1 to 5, the nozzle 14 comprises an outer section 70 and an inner
section 72 connected to the outer section 70 at the upper end (as illustrated) of the
nozzle. The outer section 70 comprises a plurality of arcuate sections which are
connected together to define an outer side wall 74 of the nozzle 14. The inner section
72 similarly comprises a plurality of arcuate sections which are each connected to a
respective section of the outer section 70 to define an annular inner side wall 76 of the
nozzle 14. The outer wall 74 extends about the inner wall 76. The inner wall 76 extends
about a central bore axis X to define a bore 78 of the nozzle. The bore axis X is
substantially orthogonal to the longitudinal axis L of the outer casing 18. The bore 78
has a generally circular cross-section which varies in diameter along the bore axis X.
The nozzle also comprises an annular upper wall 80 which extends between one end of
the outer wall 74 and one end of the inner wall 76, and an annular lower wall 82 which
extends between the other end of the outer wall 74 and the other end of the inner wall
76. The inner section 70 is connected to the outer section 72 substantially midway
along the upper wall 80, whereas the outer section 72 of the nozzle forms the majority
of the lower wall 82.
With particular reference to Figure 8, the nozzle 14 also comprises an annular air outlet
section 84. The outlet section 84 comprises an inner, generally frusto-conical inner
section 86 which is connected to the lower end of the inner wall 76. The inner section
86 tapers away from the bore axis X. In this embodiment, an angle subtended between
the inner section 86 and the bore axis X is around 15°. The outlet section 84 alsocomprises an annular outer section 88 which is connected to the lower end of the outer
section 70 of the nozzle 14, and which defines part of the annular lower wall 82 of the
nozzle. The inner section 86 and the outer section 88 of the outlet section 84 are
connected together by a plurality of webs (not shown) which serve to control the
spacing between the inner section 86 and the outer section 88 about the bore axis X.
The outlet section 84 may be formed as a single body, but it may be formed as a
plurality of components which are connected together. Alternatively, the inner section
86 may be integral with the inner section 70 and the outer section 88 may be integral
with the outer section 72. In this case, one of the inner section 86 and the outer section
88 may be formed with a plurality of spacers for engaging the other one of the inner
section 86 and the outer section 88 to control the spacing between the inner section 86
and the outer section 88 about the bore axis X.
The inner wall 76 may be considered to have a cross-sectional profile in a plane
containing the bore axis X which is in the shape of part of a surface of an airfoil. This
airfoil has a leading edge at the upper wall 80 of the nozzle, a trailing edge at the lower
wall 82 of the nozzle, and a chord line CL extending between the leading edge and the
trailing edge. In this embodiment, the chord line CL is generally parallel to the bore
axis X.
An air outlet 90 of the nozzle 14 is located between the inner section 86 and the outer
section 88 of the outlet section 84. The air outlet 90 may be considered to be located in
the lower wall 82 of the nozzle 14, adjacent to the inner wall 76 of the nozzle 14 and
thus between the chord line CL and the bore axis X, as illustrated in Figure 6. The air
outlet 90 is preferably in the form of an annular slot. The air outlet 90 is preferably
generally circular in shape, and located in a plane which is perpendicular to the bore
axis X. The air outlet 90 preferably has a relatively constant width in the range from 0.5
to 5 mm.
The annular flange 62 for connecting the nozzle 14 to the air inlet section 12 is integral
with one of the sections of the outer section 70 of the nozzle. The flange 62 may beconsidered to extend about an air inlet 92 of the nozzle for receiving the primary air
flow from the air inlet section 12. This section of the outer section 70 of the nozzle 14
is shaped to convey the primary air flow into an annular interior passage 94 of the
nozzle 14. The outer wall 74, inner wall 76, upper wall 80 and lower wall 82 of the
nozzle 14 together define the interior passage 94, which extends about the bore axis X.
The interior passage 94 has a generally rectangular cross-section in a plane which
passes through the bore axis X.
As shown in Figure 8, the air outlet section 84 comprises an air channel 96 for directing
the primary air flow through the air outlet 90. The width of the air channel 96 is
substantially the same as the width of the air outlet 90. In this embodiment the air
channel 96 extends towards the air outlet 90 in a direction D extending away from the
bore axis X so that the air channel 96 is inclined relative to the chord line CL of the
airfoil, and to the bore axis X of the nozzle 14.
The angle of inclination of the bore axis X, or the chord line CL, to the direction D may
take any value. The angle is preferably in the range from 0 to 45°. In this embodiment
the angle of inclination is substantially constant about the bore axis X, and is around
15°. The inclination of the air channel 96 to the bore axis X is thus substantially the
same as the inclination of the inner section 86 to the bore axis X.
The primary air flow is thus emitted from the nozzle 14 in a direction D which is
inclined to the bore axis X of the nozzle 14. The primary air flow is also emitted away
from the inner wall 76 of the nozzle 14. By controlling the shape of the air channel 96
so that the air channel 96 extends away from the bore axis X, the flow rate of the
combined air flow generated by the ceiling fan 10 can be increased in comparison to
that of the combined air flow generated when the primary air flow is emitted in a
direction D which is substantially parallel to the bore axis X, or which is inclined
towards the bore axis X. Without wishing to be bound by any theory we consider this
to be due to the emission of a primary air flow having an outer profile with a relatively
large surface area. In this example, the primary air flow is emitted from the nozzle 14generally in the shape of an outwardly tapering cone. This increased surface area
promotes mixing of the primary air flow with air surrounding the nozzle 14, increasing
the entrainment of the secondary air flow by the primary air flow and thereby increasing
the flow rate of the combined air flow.
Returning again to Figures 1 to 5, the support assembly 16 comprises a ceiling mount
100 for mounting the ceiling fan 10 on a ceiling C, an arm 102 having a first end
connected to the ceiling mount 100 and a second end connected to a body 104 of the
support assembly 100. The body 104 is, in turn, connected to the air inlet section 12 of
the ceiling fan 10.
The ceiling mount 100 comprises a mounting bracket 106 which is connectable to a
ceiling C of a room using screws insertable through apertures 108 in the mounting
bracket 106. With reference to Figures 9 and 10, the ceiling mount 100 further
comprises a coupling assembly for coupling a first end 110 of the arm 102 to the
mounting bracket 106. The coupling assembly comprises a coupling disc 112 which has
an annular rim 114 which is received within an annular groove 116 of the mounting
bracket 106 so that the coupling disc 112 is rotatable relative to the mounting bracket
106 about a rotational axis R. The arm 102 is inclined to the rotational axis R by an
angle Θwhich is preferably in the range from 45 to 75°, and in this example is around
60°. Consequently, as the arm 102 is rotated about the rotational axis R, the air inlet
section 102 and the nozzle orbit about the rotational axis R.
The first end 110 of the arm 102 is connected to the coupling disc 112 by a number of
coupling members 118, 120, 122 of the coupling assembly. The coupling assembly is
enclosed by an annular cap 124 which is secured to the mounting bracket 106, and
which includes an aperture through which the first end 110 of the arm 102 protrudes.
The cap 124 also surrounds an electrical junction box 126 for connection to electrical
wires for supplying power to the ceiling fan 10. An electrical cable (not shown) extends
from the junction box 126 through apertures 128, 130 formed in the coupling assembly,
and aperture 132 formed in the first end 100 of the arm, and into the air 102. Asillustrated in Figures 9 to 11, the arm 102 is tubular, and comprises a bore 134
extending along the length of the arm 102 and within which the electrical cable extends
from the ceiling mount 100 to the body 104.
The second end 136 of the arm 102 is connected to the body 104 of the support
assembly 16. The body 104 of the support assembly 16 comprises an annular inner
body section 138 and an annular outer body section 140 extending about the inner body
section 138. The inner body section 138 comprises an annular flange 142 which
engages a flange 144 located on the outer casing 18 of the air inlet section 12. An
annular connector 146, for example a C-clip, is connected to the flange 142 of the inner
body section 138 so as to extend about and support the flange 144 of the outer casing 18
so that the outer casing 18 is rotatable relative to the inner body section 138 about the
longitudinal axis L. An annular inlet seal 148 forms an air-tight seal between the shroud
36 and the flange 142 of the inner body section 138.
The air inlet section 12 and the nozzle 14, which is connected to the outer casing 18 by
the mounting bracket 58, are thus rotatable relative to the support assembly 16 about the
longitudinal axis L. This allows a user to adjust the orientation of the nozzle 14 relative
to the support assembly 16, and thus relative to a ceiling C to which the support
assembly 16 is connected. To adjust the orientation of the nozzle relative to the ceiling
C, the user pulls the nozzle 14 so that the air inlet section 12 and the nozzle 14 both
rotate about the longitudinal axis L. For example, during the summer the user may wish
to orient the nozzle 14 so that the primary air flow is emitted away from the ceiling C
and into a room so that the air flow generated by the fan provides a relatively cool
breeze for cooling a user located beneath the ceiling fan 10. During the winter however,
the user may wish to invert the nozzle 14 through 180° so that the primary air flow is
emitted towards the ceiling C to displace and circulate warm air which has risen to the
upper portions of the walls of the room, without creating a breeze directly beneath the
ceiling fan.In this example, both the air inlet section 1 and the nozzle 14 are rotatable about the
longitudinal axis L. Alternatively, the ceiling fan 10 may be arranged so that the nozzle
14 is rotatable relative to the outer casing 18, and thus relative to both the air inlet
section 12 and the support assembly 16. For example, the outer casing 18 may be
secured to the inner body section 138 by means of bolts or screws, and the nozzle 14
may be secured to the outer casing 18 in such a manner that it is rotatable relative to the
outer casing 18 about the longitudinal axis L. In this case, the manner of connection
between the nozzle 14 and the outer casing 18 may be similar to that affected between
the air inlet section 12 and the support assembly 16 in this example.
Returning to Figure 11, the inner body section 138 defines an air passage 150 for
conveying the primary air flow to the air inlet 38 of the air inlet section 12. The shroud
36 defines an air passage 152 which extends through the air inlet section 12, and the air
passage 152 of the support assembly 16 is substantially co-axial with the air passage
150 of the air inlet section 12. The air passage 150 has an air inlet 154 which is
orthogonal to the longitudinal axis L.
The inner body section 138 and the outer body section 140 together define a housing
156 of the body 104 of the support assembly 16. The housing 156 may retain a control
circuit (not shown) for supplying power to the motor 26. The electrical cable extends
through an aperture (not shown) formed in the second end 136 of the arm 102 and is
connected to the control circuit. A second electrical cable (not shown) extends from the
control circuit to the motor 26. The second electrical cable passes through an aperture
formed in the flange 142 of the inner body section 138 of the body 104 and enters the
annular channel 44 extending between the outer casing 18 and the shroud 36. The
second electrical cable subsequently extends through the diffuser to the motor 26. For
example, the second electrical cable may pass through a diffuser vane 32 of the shroud
and into the motor casing. A grommet may be located about the second electrical cable
to form an air-tight seal with the peripheral surface of an aperture formed in the shroud
36 to inhibit the leakage of air through this aperture. The body 104 may also comprise a
user interface which is connected to the control circuit for allowing the user to controlthe operation of the ceiling fan 10. For example, the user interface may comprise one or
more buttons or dials for allowing the user to activate and de-activate the motor 26, and
to control the speed of the motor 26. Alternatively, or additionally, the user interface
may comprise a sensor for receiving control signals from a remote control for
controlling the operation of the ceiling fan 10.
Depending on the radius of the outer wall 74 of the nozzle 14, the length of the arm 102
and the shape of the ceiling to which the ceiling fan 10 is connected, the distance
between the longitudinal axis L of the outer casing 18, about which the nozzle 14
rotates, and the ceiling may be shorter than the radius of the outer wall 74 of the nozzle
14, which would inhibit rotation of the nozzle through 90° about the longitudinal axis L.
In order to allow the nozzle to be inverted, the body 104 of the support assembly 16 is
pivotable relative to the arm 102 about a first pivot axis PI to move the nozzle 14
between a raised position, as illustrated in Figure 2, and a lowered position, as
illustrated in Figure 13. The first pivot axis PI is illustrated in Figure 11. The first
pivot axis PI is defined by the longitudinal axis of a pin 158 which extends through the
second end 136 of the arm 102, and which has ends retained by the inner body section
138 of the body 104. The first pivot axis PI is substantially orthogonal to the rotational
axis R about which the arm 102 rotates relative to the ceiling mount 100. The first pivot
axis PI is also substantially orthogonal to the longitudinal axis L of the outer casing 18.
In the raised position illustrated in Figure 2, the longitudinal axis L of the outer casing
18, and thus the impeller axis, is substantially parallel to the mounting bracket 106.
This can allow the nozzle 14 to be oriented so that the bore axis X is substantially
perpendicular to the longitudinal axis L and to a horizontal ceiling C to which the
ceiling fan 10 is attached. In the lowered position, the longitudinal axis L of the outer
casing 18, and thus the impeller axis, is inclined to the mounting bracket 106, preferably
by an angle of less than 90° and more preferably by an angle of less than 45°. The body
104 may be pivotable relative to the arm 102 about an angle in the range from 5 to 45°
to move the nozzle 14 from the raised position to the lowered position. Depending on
the radius of the outer wall 74 of the nozzle 14, a pivoting movement about an angle inthe range from 10 to 20° may be sufficient to lower the nozzle sufficiently to allow the
nozzle to be inverted without contacting the ceiling. In this example, the body 104 is
pivotable relative to the arm 102 about an angle of around 12 to 15° to move the nozzle
14 from the raised position to the lowered position.
The housing 156 of the body 104 also houses a releasable locking mechanism 160 for
locking the position of the body 104 relative to the arm 102. The locking mechanism
160 serves to retain the body 104 in a position whereby the nozzle is in its raised
position. With reference to Figures 11 and 12, in this example the locking mechanism
160 comprises a locking wedge 162 for engaging the second end 136 of the arm 102 and
an upper portion 164 of the body 104 to inhibit relative movement between the arm 102
and the body 104. The locking wedge 162 is connected to the inner body section 138
for pivoting movement relative thereto about a second pivot axis P2. The second pivot
axis P2 is substantially parallel to the first pivot axis PI. The locking wedge 162 is
retained in a locking position illustrated in Figure 11 by a locking arm 166 which
extends about the inner body section 138 of the body 104. A locking arm roller 168 is
rotatably connected to the upper end of the locking arm 166 to engage the locking
wedge 162, and to minimise frictional forces between the locking wedge 162 and the
locking arm 166. The locking arm 166 is connected to the inner body section 138 for
pivoting movement relative thereto about a third pivot axis P3. The third pivot axis P3
is substantially parallel to the first pivot axis PI and the second pivot axis P2. The
locking arm 166 is biased towards the position illustrated in Figure 1 1 by a resilient
element 170, preferably a spring, located between the locking arm 166 and the flange
142 of the inner body section 138.
To release the locking mechanism 160, the user pushes the locking arm 166 against the
biasing force of the resilient element 170 so as to pivot the locking arm 166 about the
third pivot axis P3. The outer body section 140 comprises a window 172 through which
a user may insert a tool to engage the locking arm 166. Alternatively, a user operable
button may be attached to the lower end of the locking arm 166 so as to protrude
through the window 172 for depression by the user. The movement of the locking arm166 about the third pivot axis P3 moves the locking arm roller 168 away from the
second end 136 of the arm 102, thereby allowing the locking wedge 162 to pivot about
the second pivot axis P2 away from its locking position and out of engagement with the
second end 136 of the arm 102. The movement of the locking wedge 162 away from its
locking position allows the body 104 to pivot relative to the arm 102 about the first
pivot axis PI and so move the nozzle 14 from its raised position to its lowered position.
Once the user has rotated the nozzle 14 about the longitudinal axis L by the desired
amount, the user can return the nozzle 14 to its raised position by lifting the end of the
nozzle 14 so that the body 104 pivots about the first pivot axis PI. As the locking arm
166 is biased towards the position illustrated in Figure 11, the return of the nozzle 14 to
its raised position causes the locking arm 166 to return automatically to the position
illustrated in Figure 11, and so return the locking wedge 162 to its locking position.
To operate the ceiling fan 10 the user depresses an appropriate button of the user
interface or the remote control. A control circuit of the user interface communicates
this action to the main control circuit, in response to which the main control circuit
activates the motor 26 to rotate the impeller 22. The rotation of the impeller 22 causes a
primary air flow to be drawn into the body 104 of the support assembly 16 through the
air inlet 150. The user may control the speed of the motor 26, and therefore the rate at
which air is drawn into the support assembly 16, using the user interface or the remote
control. The primary air flow passes sequentially along the air passage 150 of the
support assembly 16 and the air passage 152 of the air inlet section 12, to enter the
interior passage 94 of the nozzle 14.
Within the interior passage 94 of the nozzle 14, the primary air flow is divided into two
air streams which pass in opposite directions around the bore 78 of the nozzle 14. As
the air streams pass through the interior passage 94, air is emitted through the air outlet
90. As viewed in a plane passing through and containing the bore axis X, the primary
air flow is emitted through the air outlet 90 in the direction D. The emission of the
primary air flow from the air outlet 90 causes a secondary air flow to be generated bythe entrainment of air from the external environment, specifically from the region
around the nozzle. This secondary air flow combines with the primary air flow to
produce a combined, or total, air flow, or air current, projected forward from the nozzle
14.CLAIMS
1. A fan assembly for generating an air flow within a room, the fan assembly
comprising:
an air inlet section comprising an air inlet, an impeller, and a motor for rotating
the impeller about an impeller axis to draw an air flow through the air inlet;
an annular nozzle comprising an inner wall, an outer wall extending about the
inner wall, at least one air outlet for emitting the air flow, and an interior passage
located between the inner wall and the outer wall for conveying the air flow to said at
least one air outlet, the inner wall defining a bore through which air from outside the
nozzle is drawn by the air flow emitted from said at least one air outlet; and
a support assembly for supporting the air inlet section and the nozzle on a ceiling
of the room.
2. A fan assembly as claimed in claim 1, wherein the support assembly comprises a
mounting bracket which is attachable to the ceiling of the room.
3. A fan assembly as claimed in claim 2, wherein the support assembly is
configured to support the air inlet section and the nozzle so that the impeller axis is at an
angle of less than 90° to the mounting bracket.
4. A fan assembly as claimed in claim 2 or claim 3, wherein the support assembly
is configured to support the air inlet section and the nozzle so that the impeller axis is at
an angle of less than 45° to the mounting bracket.
5. A fan assembly as claimed in any of claims 2 to 4, wherein the support assembly
is configured to support the air inlet section and the nozzle so that the impeller axis is
substantially parallel to the mounting bracket.6. A fan assembly as claimed in any of claims 2 to 5, wherein the support assembly
is configured to support the air inlet section and the nozzle so that the axis of the bore is
substantially orthogonal to the mounting bracket.
7. A fan assembly as claimed in any of claims 2 to 6, wherein the nozzle and the air
inlet section are pivotable relative to the mounting bracket.
8. A fan assembly as claimed in claim 7, wherein the nozzle and the air inlet
section are pivotable about a pivot axis which is substantially orthogonal to the impeller
axis.
9. A fan assembly as claimed in any preceding claim, wherein the nozzle is
rotatable relative to the support assembly.
10. A fan assembly as claimed in claim 9, wherein the nozzle is rotatable about an
axis which is substantially co-planar with the impeller axis.
11. A fan assembly as claimed in any preceding claim, wherein the impeller axis
passes through the air inlet of the air inlet section.
12. A fan assembly as claimed in any preceding claim, wherein the impeller is an
axial flow impeller.
13. A fan assembly as claimed in any preceding claim, wherein the air inlet section
comprises a diffuser located downstream from the impeller.
14. A fan assembly as claimed in any preceding claim, wherein the air inlet section
comprises an outer casing, a shroud extending about the motor and the impeller, and a
mounting arrangement for mounting the shroud within the outer casing.15. A fan assembly as claimed in claim 14, wherein the mounting arrangement
comprises a plurality of mounts located between the outer casing and the shroud, and a
plurality of resilient elements connected between the mounts and shroud.
16. A fan assembly as claimed in claim 15, wherein the resilient elements are held in
a state of tension between the mounts and the shroud.
17. A fan assembly as claimed in any of claims 14 to 16, wherein each of the shroud
and the outer casing is substantially cylindrical.
18. A fan assembly as claimed in any preceding claim, wherein the air inlet section
is located between the support assembly and the nozzle.
19. A fan assembly as claimed in any preceding claim, wherein the support
assembly comprises an air passage located upstream of the at least one air outlet.
20. A fan assembly as claimed in claim 19, wherein the air passage is arranged to
convey an air flow towards the annular nozzle.
21. A fan assembly as claimed in claim 20, wherein the air passage is arranged to
convey air to the air inlet of the air inlet section.
22. A fan assembly as claimed in any of claims 19 to 21, wherein the impeller and
the motor are located within an air passage of the inlet section, and wherein the air
passage of the support assembly is substantially co-axial with the air passage of the air
inlet section.
23. A fan assembly as claimed in any preceding claim, wherein the support
assembly comprises a ceiling mount, an arm having a first end connected to the ceiling
mount, and a body connected to a second end of the arm and the nozzle.24. A fan assembly as claimed in claim 23, wherein the body is annular.
25. A fan assembly as claimed in claim 23 or claim 24, wherein arm is rotatably
connected to the ceiling mount.
26. A fan assembly as claimed in any preceding claim, wherein the nozzle
comprises an air outlet section extending between the inner wall and the outer wall, and
the air outlet section comprising said at least one air outlet.
27. A fan assembly as claimed in claim 26, wherein the air outlet section comprises
an inner section connected to the inner wall, and an outer section connected to the outer
wall, and wherein at least part of the inner section tapers away from the bore axis.
28. A fan assembly as claimed in claim 27, wherein an angle of inclination of said at
least part of the inner section to the bore axis is between 0 and 45°.
29. A fan assembly as claimed in claim 27 or claim 28, wherein said at least part of
the inner section has a shape which is substantially conical.
30. A fan assembly as claimed in any of claims 27 to 29, wherein said at least one
air outlet is located between the inner section and the outer section.
31. A fan assembly as claimed in any of claims 27 to 30, wherein the outer section is
substantially orthogonal to an axis of the bore.
32. A fan assembly as claimed in any preceding claim, wherein said at least one air
outlet extends about an axis of the bore.
33. A fan assembly as claimed in any preceding claim, wherein said at least one air
outlet comprises a substantially annular air outlet.34. A fan assembly as claimed in any preceding claim, wherein the air inlet section
and the nozzle have substantially the same depth in a direction parallel to the axis of the
bore.